Online music is stealing audience. But can it rival radio? “Despite numerous attempts, no one online has found a way to turn the hat trick that sustained radio through six decades of dominance of the music industry. The iTunes store is just a very alluring retailer; it has no defining personality and therefore hasn’t developed into the kind of mass community that assembled around the most successful radio DJ shows. Various adventures in file-sharing have been a bonanza for music collectors, but have done little to advance the cause of sounds that weren’t already popular.”